On Mon, 31 Jul 2017 19:57:04 -0700 Shaohua Li <s...@kernel.org> wrote:
> On Mon, Jul 31, 2017 at 04:10:07PM -0700, Stephen Hemminger wrote: > > On Mon, 31 Jul 2017 10:18:57 -0700 > > Shaohua Li <s...@kernel.org> wrote: > > > > > From: Shaohua Li <s...@fb.com> > > > > > > In a syn flooding test, the fib6_table rwlock is a significant > > > bottleneck. While converting the rwlock to rcu sounds straighforward, > > > but is very challenging if it's possible. A percpu spinlock is quite > > > trival for this problem since updating the routing table is a rare > > > event. In my test, the server receives around 1.5 Mpps in syn flooding > > > test without the patch in a dual sockets and 56-CPU system. With the > > > patch, the server receives around 3.8Mpps, and perf report doesn't show > > > the locking issue. > > > > > > Cc: Wei Wang <wei...@google.com> > > > > You just reinvented brlock... It was a long time ago (2.4) that brlock came in https://lwn.net/Articles/378781/ I removed it in 2.5.64 or so.
